The subject matter disclosed herein relates to a dual energy scan technique suitable for use in an X-ray CT apparatus.
A technique for a dual energy scan at an X-ray CT apparatus comprising one X-ray tube and one multi-row X-ray detector has been disclosed in, for example, Japanese Unexamined Patent Publication No. 2003-37778. In the dual energy scan at such a conventional X-ray CT apparatus, imaging or scanning was first conducted at a low X-ray tube voltage and the X-ray tube voltage was then raised to perform scanning at the high X-ray tube voltage. According to the present method, a time difference for raising the X-ray tube voltage has occurred between the scans. It is therefore considered that a miss registration artifact occurs due to the body motion, heartbeat, pulsation, breathing, peristalsis or the like of a subject or subject upon this scan, and thereby image quality is degraded.